The tears were real last week when members of 200 families torn asunder 50 years ago by the division of the Korean Peninsula were reunited briefly in Seoul and in Pyongyang. But many of the estimated 10,000 South Koreans with offspring in both countries may not live to see their long-lost North Korean children. A new initiative, however, could keep genealogies intact--and perhaps resolve inheritance disputes between North-South siblings.

On 1 September I.D. Gene, a Seoul-based paternity testing firm, plans to start taking saliva samples from any of the 10,000 South Korean parents who are willing. The sampling is free, but I.D. Gene will charge its usual fee (about $400) for typing the 10 nanograms or so of nuclear DNA in each sample. Efforts to get the government involved with the project have so far failed, says I.D. Gene CEO Yeon-Bo Chung, a Harvard-trained biologist. So a group of private benefactors, including the drug firm Korean Green Cross Inc., is bankrolling the estimated $80,000 sampling and storage costs.

Preserving the older generation's DNA is crucial, says Chung. That's because typing DNA from siblings alone may not cement a family connection, as siblings often have fewer DNA sequences in common with each other than with each of their parents. "Unless somebody collects the samples right now," Chung says, "they will not be available when they are desperately needed in the future."